1. Field of the Inventions
The present inventions relate to a steering-force detection device for a steering handle of a vehicle.
2. Description of the Related Art
Many conventional vehicles are steerable by operating a steering handle. Such vehicles include small planing boats, for example.
Some small planing boats are provided with a throttle lever disposed in the vicinity of a grip of the steering handle. The engine is operated to propel the boat according to operation of the throttle lever, and the moving direction of the boat is changed according to operation of the steering handle. In some conventional small planing boats, engine output can be increased by operating the steering handle, improving the steerability of the small planing boat when, for example, running at a low speed for docking (see Japanese Patent Publication JP-A-2001-329881, for example).
Such small planing boats generally include a throttle opening detection means, which detects the opening of a throttle valve that opens and closes according to operation of the throttle lever. Such small planing boats generally also include a steering angle detection means, which detects the steering angle of the steering handle, a running speed detection means, which detects the running speed of the small planing boat, and an engine output control means, which controls the engine output.
The engine output control means increases the engine's output when: a value representing the throttle opening (detected by the throttle opening detection means) is less than a predetermined value, a value representing the steering angle (detected by the steering angle detection means) is more than a predetermined value, and a value representing the running speed (detected by the running speed detection means) is more than a predetermined value.
In the foregoing conventional small planing boats, however, the degree of increase in engine output due to operation of the steering handle cannot be adjusted by the boat operator, since the engine output increases automatically when the value corresponding to the steering angle of the steering handle reaches the predetermined value.